British Airways has warned of further delays and cancellations this week as the cabin crew strike rolls into a third day with no signs of an end to the dispute that is costing the troubled flag carrier tens of millions.

The Unite union says only 300 of the 2,200 cabin crew scheduled to work during the weekend turned up. However BA says nearly 98 per cent of staff reported for work at Gatwick and over 50 percent at Heathrow.

Cabin crew plan to walk out for four days from 27 March over changes to staffing and pay. BA will unveil a revised schedule tomorrow for the strike days.

The airline has admitted that the walk-out will disrupt services even on non-strike days as aircraft and crew remain outside their usual locations. A number of planes are parked at its engineering base at Heathrow.

Monday’s services are expected to be disrupted more than at the weekend due to the higher volume of passengers scheduled to fly.

Speaking on the BA website, Walsh praised staff who had come together to keep the “flag flying”. However the airline has cancelled more than 1,000 of its 1,950 scheduled flights over the past three days, and insists that more than 60 per cent of passengers will be able to fly today.

Meanwhile Unite claims that only nine flights left Heathrow with passengers on board by mid-afternoon yesterday and that 49 long-haul flights took off without a single fare-paying passenger.

The airline’s hub, Terminal 5 at Heathrow, will remain subdued as BA tries to fly 49,000 passengers compared with the 75,000 passengers it carries on a typical March day. Many have been found seats on rival airlines.

Picket lines formed at four locations around Heathrow yesterday, with jeering when coaches with blacked-out windows passed with strike-breaking crews on board.

Tony Woodley, the joint head of Unite, attacked Mr Walsh’s “macho” management style. He said: “I am now appealing to the BA chairman and sensible members of the board to use their influence, put passengers first, and return to the negotiating table for the good of everyone,”

But there are no talks planned and it remains unclear how an end can be brought to the dispute.